Which leaves the clubs set in smaller sports markets, like Real Salt Lake, at a crossroad over the next few seasons as the league continues its hopeful transformation.
The MLS salary cap structures and rules of three designated players implemented to allow each franchise to spend above and beyond the team's considered cap remain intact.
But Dempsey's return to MLS' Seattle Sounders in August cost roughly $33 million, as reported by SI.com.
Toronto FC's shocking move for Bradley, arguably the best American player in the world at the moment, as well as English star Defoe in one fell swoop upped the ante. The Reds spent $10 million on Bradley's transfer fee alone from Italian Serie A club AS Roma. Defoe's transfer fee from Tottenham was around the same amount. Toronto reportedly spent nearly $100 million in all for the pair and just this week added Brazilian national team goalkeeper Julio Cesar.
"To be clear, these teams aren't making up money they're profitable," said RSL general manager Garth Lagerwey. "They're saying we want to go spend money on big-time players to make our league better and sell more tickets and it's a good business decision. These are not irrational choices."
Concerns over building super teams are rising among respective fan bases outside of the Seattle, L.A., New York and Toronto realms. Jason Kreis' departure to expansion club New York City FC, owned by English Premier League giant Manchester City, only furthers the nerves of how a club like RSL can stay competitive in a league aiming for stardom and cash.
"As far as the RSLs of the world are concerned, they probably are … about being able to keep up," said ESPN analyst and former L.A. Galaxy general manager Alexi Lalas, "but as long as there's only three DP spots, three players do not make a team. Even if you don't spend that kind of big money, you'll be able to compete."
Time will tell.
It took David Beckham and Landon Donovan, two of MLS' most marketable players, five seasons together before the Galaxy duo paced L.A. to back-to-back MLS Cup championships in 2011 and 2012. There is the notion that while clubs fling cash at stars, it doesn't necessarily translate to success in MLS.
"If you put Messi on the worst team in the world," Lalas said, "they'll still be the worst team in the world. Anybody can spend money yes, you have to be strategic and there's a science to it. The more difficult part is what you surround your DP players with."
RSL's two designated players are midfielder Javier Morales and forward Alvaro Saborio, whom Lagerwey, Kreis and the staff found during international scouting runs in the last seven years. The pair makes roughly $50,000 to $100,000 over RSL's cap charge, while Dempsey and Bradley will be upward of $5 million over their respective team's cap.
A former MLS goalkeeper for 11 years, RSL's first-year head coach, Jeff Cassar, remembers the days traveling to Rice-Eccles Stadium as FC Dallas' keeper and seeing the sea of empty red seats. But he said the club will have to continue to scour for difference-makers as well as the right complementary players.
"It's what's happening right now, and if MLS has dreams of being one of the top five leagues in the world," Cassar said, "then they have to do these things."
Lagerwey's competitive vision is that in five years, half of RSL's team are homegrown players out of the club's Arizona-based residential academy.
And it's achievable, he said.
"In terms of the salary-cap perspective, it will help us win games," Lagerwey said. "That's the way to put us on a level playing field with L.A. and Seattle and New York and Toronto, who are going to outspend us by tens of millions of dollars with their first team. We will get the bang for our buck by investing in our academy."